As an expert on water constructions, Gerster accompanied Lucien Bonaparte-Wyse and Lt. Armand Réclus in two expeditions in 1876-1878 commissioned to locate the most suitable route for an interoceanic canal.

The leaders of the team wrote a report claiming that s sea-level canal across the Panama Isthmus was feasible.

Gerster wrote a minority report pointing out the inadequate nature of the survey and the potential difficulties of the project, but was unable to find a publisher.

[3] After István Türr was granted permission by the Greek government to revive the long abandoned idea works of cutting through of the Corinthian Isthmus (it was Emperor Nero who first attempted this in 68 AD).

Gerster wrote about his experiences in his Hungarian-French bilingual book "A korinthusi földszoros és átmetszése" / "Cutting through the Corinthian Isthmus".